Quote from: xdigital on April 12, 2014, 01:08:32 AM

If I want to invest in bitcoin, I would buy Bitcoin rather than mining hardware.

here is my opinion
ROI analysis
Many people make decision whether the miner is worthy to buy on ROI analysis , and i will share my thought on it with you.
First, you need to consider the following two questions:
is the mining itself will disappear after six month?
What is the speed of the fastest miner can perform after six month and what is its price?

I will give you my answer to these question.
is the mining itself will disappear after six month?
The answer is definitely no, only if the bitcoin exist, no reason that mining itself will disappear, and like most of the people in the forum, i have strong faith on bitcoin.

What is the speed of the fastest miner can perform after six month and what is its price?
I cant tell you the exactly number of that, but my answer is not exceed 2T with the electricity consumption of 1000 watt, during the last one year, with the appearance of ASIC, the hash rate you can gain with 1000 watt has increased from 6G to 1000G. But it is almost the best value we can achieve based on current technology. Although i am not an professional electrical engineer, i can see that the increase of the hash rate of the chips are closely connected with its manufacturing technology, which have been increased from 110nm to 28nm by now. But as i know, it is almost achieve the limit of current chip manufacturing technology also the limit of physical law. Although 20 nm manufacturing technology is possible but the cost will also increase rapid and may be not worth to use. So we can achieve the conclusion that the life time will more than 6 month.

Now we can go forward to the second question here, what is its price.
I cannt answer this question exactly also, but i does know that its price will not below its manufacturing cost. That is very simple to understand, the factory have no reason to sell them unless they can profit. As i know, the manufacturing cost for one dragon 1T miner will not below 1000$(chip, psu, Raspberry Pi, fans, shipment fee, all these thing need cost and will not disappear) .

Now we can go back to the ROI analysis, for most of the roi analysis, it will assume one miner will only have 2-3 month life, but based on above analysis, we can see that will not happen, so there is must something wrong with the current ROI analysis.

Here is my third question, what is the the most possible number(in %) of the adjustment of difficulty for one round (12 days) in Oct 2014?
I will give my answer later, but now, i want to hear your guys opinion